[PATCH 0/2] mm/damon/core: validate damos_quota_goal->nid

[SeongJae Park <sj@kernel.org>]

node_mem[cg]_{used,free}_bp DAMOS quota goals receive the node id.  The
node id is used for si_meminfo_node() and NODE_DATA() without proper
validation.  As a result, privileged users can trigger an out of bounds
memory access using DAMON_SYSFS.  Fix the issues.

The issue was originally reported [1] with a fix by another author.  The
original author announced [2] that they will stop working including the
fix that was still in the review stage.  Hence I'm restarting this.

[1] https://lore.kernel.org/20260325073034.140353-1-objecting@objecting.org
[2] https://lore.kernel.org/20260327040924.68553-1-sj@kernel.org

Changes from RFC
(https://lore.kernel.org/20260328005412.7606-1-sj@kernel.org)
- fix typo in patch 2: s/MEM/MEMCG/.
- rebase to latest mm-new.

SeongJae Park (2):
  mm/damon/core: validate damos_quota_goal->nid for
    node_mem_{used,free}_bp
  mm/damon/core: validate damos_quota_goal->nid for
    node_memcg_{used,free}_bp

 mm/damon/core.c | 19 +++++++++++++++++++
 1 file changed, 19 insertions(+)


base-commit: 2f8cc7995d75c89079c55a85fc1d3092ffb7bd59
-- 
2.47.3